US-France Workshop to Establish an International Collaboration for the Strateole-2 Campaign on Science of the Equatorial Upper Troposphere / Lower Stratosphere

University Of California-San Diego Scripps Inst Of Oceanography, La Jolla CA

Investigators

Abstract

a non-technical explanation This project will support a team of scientists from several US universities and research institutes to participate in a 3-day workshop in France to establish a new international research collaboration for science of the Tropical Upper Troposphere / Lower Stratosphere (UT/LS). The new understanding of the dynamics, chemistry, and momentum exchange between the troposphere and stratosphere gained from Strateole 2 is critical for the new generation of climate models that extend as high as 1 hPa and attempt to incorporate variability in the stratosphere into our understanding of climate change. The workshop will also provide an opportunity for a group of undergraduate physics and engineering students from Puerto Rico interested in balloon platforms to learn about key motivations for stratospheric research, and get a new perspective on engineering challenges for making these types of measurements. a technical description Stratospheric water vapor plays an important role in the radiative budget of the stratosphere as well as in modulating surface warming. The tropical tropopause layer (TTL) is often referred to as the gateway to the global stratosphere, however there are still debates on the chemical transport pathways and how moist air is transported upward and eventually dehydrated in the TTL. The objectives of the research are to 1) determine the roles of tropical waves and deep convection on the transport of water vapor into the stratosphere and formation of cirrus clouds in the tropical tropopause layer, 2) understand the relative roles of planetary-scale waves through small scale gravity waves in the forcing of the quasi-biennial oscillation, 3) characterize background aerosol loading, aerosol size distributions, and ozone chemistry in the tropical lower stratosphere to constrain this transport. New superpressure balloon instrumentation, including a fiber-optic temperature profiler, new pico-SDLA diode laser measurements of water vapor and lightweight frost point hygrometers that measure in-situ cold point temperatures and water vapor with unprecedented accuracy, will be key to new advances in this field.